Deficit of interleukin-7 in serum of patients with Crohn's disease

Serum cytokines MCP-1 and GCS-F as potential biomarkers in pediatric inflammatory bowel disease

BACKGROUND

Inflammatory bowel diseases (IBDs) with the subtypes ulcerative colitis (UC) and Crohn disease (CD), are chronic autoimmune inflammatory disorders of the gastrointestinal tract. Cytokines are associated with the development and progression in pediatric IBD. We measured cytokine levels in pediatric IBD patients to assess their potential function as biomarkers in disease assessment.

METHOD

In this prospective cohort study, we enrolled 33 children with IBD. All patients were in stable remission for 3 months on enrollment. Patients who developed a relapse within six months after enrollment were classified as relapsers. Blood sampling was performed at enrolment and for relapsers in relapse and post-relapse. Serum concentrations of 14 cytokines, chemokines and growth factors (IL-1α, IL-1β, IL-6, IL-12p40, IP-10, TNF-α, IFN-γ, IL-10, IL-8, MIP-1α, MCP-1, MCP-3, G-CSF, GM-CSF) were measured simultaneously using multiplex bead-based sandwich immunoassay on Luminex 100 system.

RESULTS

MCP-1 was significantly higher in CD patients compared to UC patients at each disease stage: stable remission (P<0.048), unstable remission (P<0.013), relapse (P<0.026) and post-relapse (P<0.024). G-CSF was significantly increased in UC patients developing a relapse and in post-relapse stage compared to UC patients in remission (P<0.02 and p<0.03, respectively).

CONCLUSION

MCP-1 showed potential as a diagnostic biomarker in CD patients independent of disease activity as it was able to discriminate between subtypes of pediatric IBD. In UC patients, G-CSF was significantly elevated in relapsers indicating its use and role as a potential prognostic biomarker.

Serological cytokine signature in paediatric patients with inflammatory bowel disease impacts diagnosis

Endoscopy is a central tool for diagnosing and evaluating paediatric inflammatory bowel diseases (PIBD), but is too invasive to be frequently repeated in young children. Furthermore, it is challenging to distinguish Crohn’s disease (CD) from ulcerative colitis (UC) endoscopically. This study aimed to determine biomarkers useful for the diagnosis of PIBD. Cytokines, chemokines, and growth factors were quantified in the sera of 15 patients with CD or UC, at disease onset prior to treatment, and 26 age-matched controls. Correlation of cytokine levels with the paediatric CD activity index (PCDAI) and the paediatric UC activity index (PUCAI) was analysed. Interleukin (IL)-6, IL-13, IL-7, and vascular endothelial growth factor were higher in the CD group than in the UC group. The receiver operating characteristic curve analysis showed that IL-7 was a putative biomarker for distinguishing CD from UC (area under the curve: 0.94). Granulocyte–macrophage colony-stimulating factor was associated with PCDAI, and an IL-1 receptor antagonist, IL-6, and macrophage inflammatory protein-1β were associated with PUCAI. These findings indicate significant differences in cytokine signatures among patients with new-onset PIBD, which may improve accuracy in diagnosing PIBD.

Gammadelta T Cells in Crohn's Disease: A New Player in the Disease Pathogenesis?

Crohn's disease [CD] is a chronic relapsing systemic disease affecting the gastrointestinal tract. An altered immune response to commensal intestinal bacteria takes place in genetically predisposed individuals, resulting in chronic inflammation in the gut. Several alterations in the innate immunity mechanisms have been described in recent years. Thus, the study of the immunological aspects of CD, specifically the role of lymphocytes, is a key element for understanding the pathogenesis of the disease.Gammadelta T cells [γδ T cells] constitute only a small proportion of the lymphocytes that circulate in the blood and peripheral organs and they are present mainly in the epithelia, where they can constitute up to 40% of intraepithelial lymphocytes [IEL] in the intestinal mucosa. Due to their lack of major histocompatibility complex [MHC] restriction and their unique plasticity and immune-regulating properties, they are considered key cells in the first line of defence against infections and in wound healing in the gut. Although there is growing experimental and clinical evidence of their implication in inflammatory bowel disease [IBD], including CD, their clinical relevance is still unclear.In this review, we address the possible involvement of γδ T cells in the pathogenesis of CD, reviewing their role against infections and in inflammation and the current evidence suggesting their implication in CD, offering a novel potential target for immunotherapy in IBD.

Curcumin Anti-Apoptotic Action in a Model of Intestinal Epithelial Inflammatory Damage

The purpose of this study is to determine if a preventive treatment with curcumin can protect intestinal epithelial cells from inflammatory damage induced by IFNγ. To achieve this goal we have used a human intestinal epithelial cell line (HT29) treated with IFNγ to undergo apoptotic changes that can reproduce the damage of intestinal epithelia exposed to inflammatory cytokines. In this model, we measured the effect of curcumin (curcuminoid from Curcuma Longa) added as a pre-treatment at different time intervals before stimulation with IFNγ. Curcumin administration to HT29 culture before the inflammatory stimulus IFNγ reduced the cell apoptosis rate. This effect gradually declined with the reduction of the curcumin pre-incubation time. This anti-apoptotic action by curcumin pre-treatment was paralleled by a reduction of secreted IL7 in the HT29 culture media, while there was no relevant change in the other cytokine levels. Even though curcumin pre-administration did not impact the activation of the NF-κB pathway, a slight effect on the phosphorylation of proteins in this inflammatory signaling pathway was observed. In conclusion, curcumin pre-treatment can protect intestinal cells from inflammatory damage. These results can be the basis for studying the preventive role of curcumin in inflammatory bowel diseases.

Characterization of Serum Cytokine Profile in Predominantly Colonic Inflammatory Bowel Disease to Delineate Ulcerative and Crohn's Colitides

BACKGROUND

As accessible diagnostic approaches fail to differentiate between ulcerative colitis (UC) and Crohn’s colitis (CC) in one-third of patients with predominantly colonic inflammatory bowel disease (IBD), leading to inappropriate therapy, we aim to investigate the serum cytokine levels in these patients in search of molecular biometric markers delineating UC from CC.

METHODS

We measured 38 cytokines, chemokines, and growth factors using magnetic-bead-based multiplex immunoassay in 25 UC patients, 28 CC patients, and 30 controls. Our results are compared with those from a review of current literature regarding advances in serum cytokine profiles and associated challenges preventing their use for diagnostic/prognostic purposes.

RESULTS

Univariate analysis showed statistically significant increases of eotaxin, GRO, and TNF-α in UC patients compared to controls (Ctrl); interferon γ, interleukin (IL)-6, and IL-7 in CC group compared to Ctrl; and IL-8 in both UC and CC versus Ctrl. No cytokines were found to be different between UC and CC. A generalized linear model identified combinations of cytokines, allowing the identification of UC and CC patients, with area under the curve (AUC) = 0.936, as determined with receiver operating characteristic (ROC) analysis.

CONCLUSIONS

The current knowledge available about circulating cytokines in IBD is often contradictory. The development of an evidence-based tool using cytokines for diagnostic accuracy is still preliminary.

Interleukin-7 is decreased and maybe plays a pro-inflammatory function in primary immune thrombocytopenia

Primary immune thrombocytopenia (ITP) is an autoimmune disease with many immune dysfunctions, including over-proliferation and apoptosis resistance of auto-reactive lymphocytes. This study aimed to determine the effects of interleukin (IL)-7 on the cytokine production and survival of peripheral blood mononuclear cells and bone marrow mononuclear cells from ITP patients. We found that the plasma IL-7 levels in peripheral blood from ITP patients were lower than that of the normal controls, and it had positive correlation with platelet counts. However, the levels of IL-7 did not change in bone marrow serum of ITP patients compared with that of normal controls. The result of further stimulation experiments in vitro showed that IL-7 up-regulated the apoptosis of autologous platelets, promoted the proliferation and secretion of interferon-γ, tumor necrosis factor-α as well as IL-10 of lymphocyte both from peripheral blood and bone marrow. As the role of IL-7 in apoptosis-resistance and stimulation of pro-inflammatory cytokines, we speculated that decreased IL-7 in peripheral blood, maybe, is a consequence of the negative feedback of the pro-inflammatory function in ITP patients.

Cytokines as biomarkers in rheumatoid arthritis

RA is a complex disease that develops as a series of events often referred to as disease continuum. RA would benefit from novel biomarker development for diagnosis where new biomarkers are still needed (even if progresses have been made with the inclusion of ACPA into the ACR/EULAR 2010 diagnostic criteria) and for prognostic notably in at risk of evolution patients with autoantibody-positive arthralgia. Risk biomarkers for rapid evolution or cardiovascular complications are also highly desirable. Monitoring biomarkers would be useful in predicting relapse. Finally, predictive biomarkers for therapy outcome would allow tailoring therapy to the individual. Increasing numbers of cytokines have been involved in RA pathology. Many have the potential as biomarkers in RA especially as their clinical utility is already established in other diseases and could be easily transferable to rheumatology. We will review the current knowledge's relation to cytokine used as biomarker in RA. However, given the complexity and heterogeneous nature of RA, it is unlikely that a single cytokine may provide sufficient discrimination; therefore multiple biomarker signatures may represent more realistic approach for the future of personalised medicine in RA.

Microsporidia and its relation to Crohn's disease. A retrospective study

BACKGROUND

The cause of Crohn's Disease (CD) remains unknown. Recently a decrease in the global lymphocyte population in the peripheral blood of CD patients has been reported. This decrease was more evident in γδ T lymphocytes, especially γδ CD8+T subsets. Furthermore, a decrease of IL-7 was also observed in these patients. We propose the hypothesis that microsporidia, an obligate intracellular opportunistic parasite recently related to fungi, in CD patients can take advantage of the lymphocytes and IL-7 deficits to proliferate and to contribute to the pathophysiology of this disease.

METHODS AND FINDINGS

In this case-control study, serum samples were collected from 36 CD patients and from 36 healthy individuals (controls), IgE and IgG anti-Encephalitozoon antibodies were determined by ELISA; and forty-four intestinal tissue samples were analyzed through real time Polymerase Chain Reaction (PCR), twenty CD patients, nine with others diseases and 15 healthy subjects. We observed that IgE anti-Encephalitozoon levels were significantly higher in patients with CD: 0.386(±0.256) vs control group, 0.201(±0.147), P<0.001. However, IgG anti-Encephalitozoon values were significantly lower in CD patients: 0.361(±0.256) vs control group, 0.876(±0.380), P<0.001. In the group of CD patients, 6/20 (30%) were positive by real time PCR for microsporidia and, all the patients of the control group were negative by real time PCR.

CONCLUSIONS

These results suggest that CD patients are a group at risk for microsporidiasis and, moreover that microsporidia may be involved as a possible etiologic factor of CD.